Some Spitfire variants have clipped wingtips instead of the round, elliptical wingtip. The reason for this is to increase the roll rate and low-altitude performance. My question is: How would clipping the wings of an aircraft increase its low altitude performance?
It would increase the roll rate, and it would increase the maximum possible airspeed at lower altitudes. Generally speaking, decreasing the wing loading doesn't help to maximize the achievable airspeed unless an aircraft is near its service ceiling. At low altitudes, increasing the wing loading by reducing the wing area often increases the maximum achievable airspeed, by reducing profile drag.
As Pierre Henri Clostermann says in his "Grand Cirque":
Spitfire V: nickname:clipped,cropped,clapped
Clipped = tip of clipped wings
- Advantage:increased speed and lateral maneuverability. wings reduced by about one meter.
- Disadvantages: this reduces the bearing surface and increases the marginal vortices
- the RR Merlin's compressor rotates faster, and increases the intake pressure ... This has the effect of increasing the amount of air entering the engine, while the displacement remains the same. The Merlin of these series (around 40) gives around 1,650 CV at ground level, while the XX series (approx.) Of the classic Spitfire Mk.V give only 1,200 (below 10 000m)
- The downside is that is that an inflated engine is less reliable and it lasts less time
Other disadvantages: that at 3500 m=50 cv and the guns have only 60 shells each against 145 in the Spitfire IX!
- personal appreciation of the time ... of the pilots !!!
It apparently increased the roll rate of the aircraft and made a more optimal design for low altitude operations and ‘air-to-mud’ work happening more and more near the end of the war. The cropped wing Spits were often paired with superchargers equipped with cropped impellers optimized for lower altitude flight, though this was not always the case. It also improved manufacturability over elliptical wing Spits.